It is standard for a bottle (the term here intended to cover any vessel having an upwardly open normally capped neck) to be picked up off a conveyor after it has been filled and capped or to be picked from a case or carton and deposited on such a conveyor by a piece of automatic equipment having a pickup device. Such a device normally engages down over the capped neck of the bottle and then into engagement with the sides of the neck with sufficient force that, once the device is lifted, the bottle comes with it.
In the normal embodiment of such a device a relatively thin elastic cuff is provided inside the grab and is connected to a source of fluid, normally air, under pressure. The cuff is inflated so that its inner periphery bears on the bottle's neck. Such an arrangement can readily accommodate minor variations in neck size and bottle position, and can even lift a bottle that has no cap.
The main disadvantage of such an arrangement is that the cuff can be damaged fairly easily. A standard crown top has sufficient sharp edges to rapidly wear out the cuff, and a tamperproof screw cap also is irregular enough to present a danger to the cuff. If the cap is missing and the bottle neck is broken, which is a not uncommon occurrence, puncturing of the cuff is highly likely.
Making the cuff fairly thick and durable does lessen the likelihood of it being punctured, but means that the device must be operated at substantially higher pressure in order to provide the necessary holding force. Even with such a thicker cuff, the slightest puncture renders the device useless, and replacing the cuff is a fairly complex operation entailing substantial disassembly of the equipment.